WASHINGTON, D.C.: Mike Synar, Oklahoma Democrat and 16-year veteran of Congress, died today at home of a brain tumor. He was just 45 years old. A feisty liberal who tirelessly battled the gun and tobacco lobbies, he nonetheless represented a district peopled mostly by conservative Democrats who favor gun rights and deregulation. "I always admired Harry S. Truman," Synar told the Associated Press in 1994. "He fought special interests, and he told it like it was." So did Synar, generally. He railed against the widely popular Gramm-Rudman law designed to prevent deficit spending during the 1980s. President Clinton today paid tribute to Synar, calling him "a brave and unflinching public servant who in tough political times remained true to his principles." Those principles ultimately proved too liberal for Synar's constituents. Synar lost the 1994 primary to a retired teacher with just $19,000 to spend. After that defeat, Synar remained in Washington to pursue political causes, and was awarded the 1995 Profile in Courage Award from the John F. Kennedy Library.